24V input ceiling, 2–4 cell Li-Ion — I²C-programmed charging
The BQ24725RGRR is a Texas Instruments Li-Ion battery charger IC that handles 2 to 4 series cells with a maximum battery pack voltage of 19.2V and a supply input rated up to 24V. Charging current is constant and programmable via the I²C interface — no external sense resistor divider needed for current setting. Fault protection is on-chip: overcurrent, overvoltage, and short-circuit detection are included, reducing the external component count for a production BOM.
I²C bus sets the charge profile — firmware owns the loop
Charge current and voltage are written over the I²C bus, so the system microcontroller or embedded controller manages the charging algorithm. No potentiometer or resistor-divider network on the charge-voltage feedback pin — the firmware controls the taper and termination.
For dual-sourcing, evaluate the BQ24725 family pin-compatible variants; confirm the I²C register map and protection thresholds match your firmware driver.